Turkish foreign minister says borders of Syrian rebel-held province will be protected under deal signed with Russia.

Turkey's foreign minister says no civilians will be removed from Syria's northwestern Idlib province under a deal signed by Ankara and Moscow to create a demilitarised zone in the area.

"The borders of Idlib will be protected under the memorandum of understanding signed in Sochi. There would be no change in the status of Idlib," Mevlut Cavusoglu said on Tuesday, adding that merely "terrorist" groups were to be removed from the area.

The agreement to halt plans for an offensive on the last major rebel-held stronghold was announced in the Black Sea resort of Sochi on Monday after a meeting between the Russian President Vladimir Putin and his Turkish counterpart, Recep Tayyip Erdogan.

On Tuesday, Iran's foreign minister hailed the agreement over the rebel-held province, calling it an example of "responsible diplomacy".

On his Twitter account, Zarif wrote: "Intensive responsible diplomacy over the last few weeks-pursued in my visits to Ankara & Damascus, followed by the Iran-Russia-Turkey Summit in Tehran and the meeting [in] Sochi-is succeeding to avert war in #Idlib with a firm commitment to fight extremist terror. Diplomacy works."

Later on Tuesday, European Union Spokesperson Maja Kocijancic stressed that the Turkish-Russian deal must protect civilians and ensure humanitarian access.

"We expect that the agreement which was according to reports reached yesterday by the Russian and Turkish presidents will guarantee the protection of civilian lives and infrastructure as well as guarantee unhindered and sustainable humanitarian access," Kocijancic told reporters.

Iran has fought as an ally of President Bashar al-Assad in the Syrian conflict alongside Russian forces, while Turkey supported certain rebel groups during the seven-year-old civil war.

'Withdrawal in October'

Announcing the deal alongside Erdogan on Monday, Putin said the 15-20km-wide zone would be established by October 15.

Putin said that heavy weapons would be withdrawn from all opposition forces by October 10 - a move supported by the Syrian government.

Describing the agreement as a "serious result", Putin said that "Russia and Turkey have confirmed their determination to counter terrorism in Syria in all its forms".

For his part, Erdogan said both his country and Russia would carry out coordinated patrols in the demilitarised zone.

"We decided on the establishment of a region that is cleaned of weapons between the areas which are under the control of the opposition and the regime," said Erdogan.

The Syrian government had recently announced plans to launch a major military offensive on Idlib province, long controlled by various armed opposition groups, after managing to claw back swaths of rebel-held territory.

Since the beginning of September, dozens of people have been killed and wounded in air raids and attacks by the Syrian government and allied Russian fighter jets, according to activists on the ground.

Over the past week, Turkey has deployed reinforcements and expanded defensive structures at a dozen observation points across opposition-held territories in Idlib, western Aleppo, and northern Hama provinces.

The outposts were established after a "de-escalation" agreement was reached between Turkey, Russia, and Iran in July 2017.